Perfluorochemicals in the form of emulsions are being made to dissolve as much oxygen and carbon dioxide as whole blood. When infused intravenously after partial phlebotomy, high venous and tissue oxygen tensions are found in oxygen-breathing animals. Most survived in good health after infusion of artificial blood. Primates, such as rhesus monkeys and baboons, are being used, as well as mice, rats, cats, and dogs, in these studies. The less natural blood that is present when the emulsion is infused in the animal, the longer it stays in the blood stream, but it is finally all phagocytosed and deposited mainly in the liver and spleen. Many fluorochemicals remain in the liver for the lifetime of the animal but all the isomers of at least two fluorocarbons, perfluorodecalin and perfluoromethyldecalin leave in a few weeks with no apparent harm to the liver. Purity of the compound studied has been the major problem encountered. Perfluorodecalin, which we have selected as the major compound to study intensively, is purified by spinning band distillation and/or by preparative gas chromatography. Emulsions are made in the Gaulin homogenizer, as sufficient quantities are available; otherwise sonication is used. A screening method is used where: a) it is determined if perfluorochemicals can be emulsified; b) it is tested for acute intravenous toxicity in mice; c) it is tested for physiological effects in dogs; and d) it is tested for acute physiological and chronic effects in non-human primates. Chemical and biological methods are used. In addition to the decalin and adamantane, a large number of cyclic and aliphatic compounds are being evaluated. BIBLIOGRAPHIC REFERENCES: Clark, Leland C., Jr., Eugene P. Wesseler, Samuel Kaplan, Robert Moore, Donald Denson and Carolyn Emory. Intravenous infusion of cis-trans perfluorodecalin emulsions in the rhesus monkey. In: Biochemistry Involving the Carbon-Fluorine Bond, edited by Robert Filler: American Chemical Society Symposium Series, No. 28, Chapter 8, Washington, D.C., 135-170 (1976). Miller, Marian L., Leland C. Clark, Jr. and Steven C. Jones. Some morphologic effects of "inert" particulate loading on hemopoietic elements in mice. Submitted May, 1976 to the Journal of the Reticuloendothelial Society.